Surveillance cameras are currently used in many different applications, for monitoring environments both indoors and outdoors. Cameras may e.g. be used for monitoring areas where a person is serving customers from behind a counter, and where the inside of the counter may be used as storage for items or equipment where access should be restricted to the person manning the counter. Examples of such environments could be hotel front desks, bank office counters, reception desks, bars, fast food counters, cashier desks at gas stations, or check-in counters at airports. Another example is shops or boutiques selling perfume, jewelry or wrist watches over a staffed counter. When the person working at the desk or counter is serving a customer, it might be difficult for him or her to keep track of other persons approaching the desk and potentially trying to gain access to items and equipment only meant to be handled by the person working at the counter. It would be therefore be desirable to provide improved solutions for assisting staff manning a counter to prevent unauthorized access to areas behind the counter.